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1.
The numerical simulation of comparative elastohydrodynamic lubrication between axisymmetrical and 3D elastic approaches on the radial lip seals is presented in order to determine the 3D effect of the elastic aspect of the seal lip. Indeed, the consideration of 3D model in other words the circumferential variation of the lip elastic deformation indicated a difference in the deformation distribution of the lip compared to the axisymmetrical approach. Consequently, the results show that the presence of the circumferential variation of the seal lip deformation has a significant effect on the pumping rate values.  相似文献   
2.
A new fringe tracker based on photon-counting detectors and real-time image processing has been implemented on the Grand Interféromètre à 2 Télescopes at the Observatoire de la Cote d'Azur. Fringe visibilities have been recorded on P Cygni and other stars across the Hαemission line with optical path differences stabilized to between 4 and 7 μm rms (1% of the coherence length). We present our initial results and describe the principle, implementation, and performance of the fringe tracker.  相似文献   
3.
Intra-articular drug delivery systems (DDSs) are envisaged as interesting alternative to locally release non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen to reduce pain in patients with osteoarthritis. The present study examines the efficacy of S-(+)-ibuprofen on cartilage degradation as drug candidate for DDS loading. Humeral cartilage and joint capsule explants were collected from healthy sheep shoulder joints and they were cultured in mono- or in co-culture for 13?days with LPS in combination with S-(+)-ibuprofen at 50?µM and 1?mM. S-(+)-ibuprofen (50?µM) blocked prostaglandins production in LPS-activated explants but did not reduce cartilage degradation. By contrast, 1?mM S-(+)-ibuprofen treatment of cartilage explants reduced nitric oxide synthesis by 51% (p?=?0.0072), proteoglycans degradation by 35% (p?=?0.0114) and expression of serum amyloid protein – the main protein induced upon LPS challenge – by 44% (p?相似文献   
4.
The present paper reviews the available information on the eating quality of pork from the perspective of production systems considered at farm level. Among the specifications differentiating systems having a claim on eating quality, breed, feeding strategy, rearing conditions and slaughter age/weight of the pigs may influence pork eating quality. Specific genetic X environment interactions such as the use of slow growing-fat local breeds reared in extensive conditions, as encountered in local Mediterranean systems, lead to high eating quality of pork and pork products Organic production per se has little influence on the eating quality of pork. Welfare-oriented specifications such as enriched living environment, outdoor access or free-range rearing have limited consequences on pork quality. Because boar taint negatively impacts the consumer acceptability of pork, a total ban on castration to improve animal welfare would be a real challenge for the management of pork quality in those countries where entire male pig production is not currently common.  相似文献   
5.
We present a multiresolution morphing algorithm using ``as-rigid-as-possible' shape interpolation combined with an angle-length based multiresolution decomposition of simple 2D piecewise curves. This novel multiresolution representation is defined intrinsically and has the advantage that the details' orientation follows any deformation naturally. The multiresolution morphing algorithm consists of transforming separately the coarse and detail coefficients of the multiresolution decomposition. Thus all LoD (level of detail) applications like LoD display, compression, LoD editing etc. can be applied directly to all morphs without any extra computation. Furthermore, the algorithm can robustly morph between very large size polygons with many local details as illustrated in numerous figures. The intermediate morphs behave natural and least-distorting due to the particular intrinsic multiresolution representation.  相似文献   
6.
Volume Preservation of Multiresolution Meshes   总被引:4,自引:0,他引:4  
Geometric constraints have proved to be efficient for enhancing the realism of shape animation. The present paper addresses the computation and the preservation of the volume enclosed by multiresolution meshes. A wavelet based representation allows the mesh to be handled at any level of resolution. The key contribution is the calculation of the volume as a trilinear form with respect to the multiresolution coefficients. Efficiency is reached thanks to the pre-processing of a sparse 3D data structure involving the transposition of the filters while represented as a lifting scheme. A versatile and interactive method for preserving the volume during a deformation process is then proposed. It is based on a quadratic minimization subject to a linearization of the volume constraint. A closed form of the solution is derived.  相似文献   
7.
Reactive powder concrete (RPC) is a new cement-based material developed through microstructural engineering. RPC is composed of very fine powders: sand, crushed quartz and silica fume, all with particle sizes comprised between 300 and 0.02 μm, and a low water content, W/C<0.20. A very dense matrix is achieved by optimizing the granular packing of these powders. This compactness confers to RPC ultrahigh strength and durability.

The hydration kinetic of the cementitious matrix using electrical conductivity and isothermal calorimetry is presented. A linear relationship between the logarithm of conductivity ln(σ) and the degree of hydration , has been found:

ln(σ)=AvBv
where Av depends on the nature and the dosage of the different mineral and organic components, and Bv is an invariant related to the granular packing. From 19 different RPC compositions, an average value of 12.1 with a standard deviation of 1.7 were found for Bv. The capillary porosity percolation threshold was also deduced from this relationship. It has been found that when the degree of hydration is equal to 26%, the capillary pore space is discontinuous. This last result is in agreement with the prediction of the NIST microstructural model by Bentz and Garboczi [D., Bentz, E. Garboczi, Percolation of phases in a three-dimensional cement paste microstructural model, Cem Concr Res 21 (2) (1991) 325–344]. A continuous determination of the degree of hydration based on electrical conductivity is proposed.  相似文献   
8.
A preprocessor has been designed for signal acquisition and compression and applied in the context of ambulatory ECG processing. The interface uses four microprocessors to perform accelerated data acquisition and encoding of two simultaneous ECG signals at up to 60 times real time. The encoding is made along the well-known AZTEC algorithm. Although designed specifically to interface to the UNIBUS of a PDP-l1 minicomputer, generality of the approach ensures easy implementation of the board on other popular minicomputers.  相似文献   
9.
Most of the male piglets in the EU are castrated. According to the current EU legislation, surgical castration can be performed without anaesthesia up to the age of 7 days. A report of the European Food Safety Authority (EFSA) on the welfare aspects in relation to the castration of pigs has underlined the need for further research. As a follow up, the EU has launched a two-year project (Specific Support Action PIGCAS) within the 6th EU Framework Programme, starting in January 2007. “PIGCAS” is the acronym for “Attitudes, practices and state of the art regarding piglet castration in Europe”. The main objectives are: [A] to collect information on the attitudes of the various stakeholders (consumer groups, NGOs and industry stakeholders); [B] to collect information on the extent of the practice of castration of piglets (male or female) within the EU and the conditions under which castration is performed; [C] to evaluate research work and other sources of information, in order to examine surgical castration without anaesthesia and its possible alternatives from different perspectives and derive research priorities; and [D] to integrate the collected information and evaluation in a report providing support for EU policy in the field of research and legislation. Preliminary results are now available on objectives [A] and [B]. When referring to the alternatives to surgical castration, one has to distinguish between short-term and long-term solutions. Surgical castration with anaesthesia was mentioned by most of the stakeholders as a short-term alternative. Genetic control of boar taint and sperm sexing to select only females for pork production are considered as long-term alternatives. Current practices of castration and levels of acceptability vary substantially between and within countries and regions. The current research focuses on practical methods for acute and postoperative pain alleviation and analyses the complex consequences of raising entire males or immunocastrated boars. Considering the different dimensions (attitudes, extent of practice, animal welfare, pork quality and economy) of importance, it is intended to propose to the EU short and long-term strategies to handle this problem.

Eingegangen: 26. Februar 2008; angenommen: 29. Februar 2008  相似文献   
10.
A lack of nutritious food during the first year of life is a hypothesized factor that may limit survival of endangered pallid sturgeon Scaphirhynchus albus in the lower Missouri River (LMOR). Unfortunately, information for age‐0 pallid sturgeon diets remains limited, but diet analyses for age‐0 Scaphirhynchus spp. (sturgeon hereafter) have occurred. Little information, however, exists on age‐0 sturgeon diets in the LMOR; thus, our primary objective was to document age‐0 sturgeon diets in this system. We examined guts contents from 30 individuals, which were genetically identified as shovelnose sturgeon Scaphirhynchus platorynchus, and three stomachs were empty. The remaining age‐0 shovelnose sturgeon consumed chironomid larvae almost exclusively (>98% of prey items consumed). Our results were similar to studies conducted in other systems, and it appears unlikely that a lack of nutritious food was a major factor affecting the individuals captured during this study. This effort provides important information to help guide ongoing adaptive management efforts in the LMOR. © 2016 The Authors. River Research and Applications published by John Wiley & Sons Ltd.  相似文献   
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